Physics: Post your doubts here!

[Unicorn]

Guys can someone help me please. My AS practical exam is in 2 days and the teacher told us that 90% chance that electricty (judging by previous papers) is not coming which leaves only mechanical physics (don't scream and shout if electricty comes) . So i have a few questions

1) when attaching springs in series do you measure the extension of 1 spring or all of them?
2) when attching springs in parallel do you take the average extension of the springs because they all don't extend by same amount exactly

Thanks

 

[code11]

if the distance between the double slits is increased ,while other things are constant,what is the effect on fringe sepration and brightness of frings ?

 

[Unicorn]

if the distance between the double slits is increased ,while other things are constant,what is the effect on fringe sepration and brightness of frings ?

well the sepration will be halved and so will the brightness i presume

 

[Oliveme]

Please help me with this question In physics paper 23, question 2 part (c). I have no idea about vector triangles. http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_s10_qp_23.pdf

Thank you very much.

 

[mushoo]

can we take out the y- intercpt of the graphs of the practical, by using the equation?? :/

 

[hmlahori]

Can someone explain these paper 2 questions?

http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_w05_qp_2.pdf
http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_w05_ms_2.pdf
Q2(b) and Q4(b ii)

 

[geek101]

• Can someone please say the uncertainty, error and the uncertainty we use when calculating the % uncertainty for a meter rule, a vernier caliper and a stopwatch?? thank you...and good luck folks!

 

[Winson0920]

can someone tell me,should I leave my answer in MM or CM?
the CIE marks scheme are usually checking with MM...
eg. 9702_w11_ms_33.pdf

 

[hmlahori]

Can someone explain these questions as well as the ones i posted above.

http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s06_qp_2.pdf
http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s06_ms_2.pdf
Q2(c) and Q7(a) I get how its lamp C which is faulty but how can we know that it is shorted?

 

[code11]

Can someone explain these questions as well as the ones i posted above.

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s06_qp_2.pdf
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s06_ms_2.pdf
Q2(c) and Q7(a) I get how its lamp C which is faulty but how can we know that it is shorted?

u aint preparing for physics practical ? :O

 

[hmlahori]

u aint preparing for physics practical ? :O

my physics practical is on the 31 may and i have physics P2 and many other papers before that so ya not rite now.......

 

[code11]

my physics practical is on the 31 may and i have physics P2 and many other papers before that so ya not rite now.......

hmm oky gud luck .my practical tomorow

 

[mushoo]

hmm oky gud luck .my practical tomorow

hey, i need to kno a thng abt prac.
ie, can we find out the y-intercept of a graph, by the formula? :/
Rep asap!

 

[Unicorn]

hmm oky gud luck .my practical tomorow

good luck

 

[Unicorn]

hey, i need to kno a thng abt prac.
ie, can we find out the y-intercept of a graph, by the formula? :/
Rep asap!

well that varies from each formula if they tell u to graph T^2 as y axis and lets say 1/d as x-axis

and the formula is T^2=4kl/d +5c

then you would know that T^2 is y value
4kl is gradient
1/d is x axis
5c would be the y-intecept value

when they give u a formula try to work out where y, x, m and c are

 

[code11]

hey, i need to kno a thng abt prac.
ie, can we find out the y-intercept of a graph, by the formula? :/
Rep asap!

yes we can

 

[A.ELWY 7]

how to find a phase difference???:S

it is either by giving the answer as ( pie rad) or the degree..well lets say that one wavelength (lambda) is equal to half pie..where it is equal to 180 degree,(u must memorize this) then u logically must know that to have 1 pie, then the wavelength must be 2 lambda ..and so it is 360 degree etc..to know the phase difference in a staionary wave measure the wavelength between the 2 points you r asked for, and then the rest is easy
note:if i said anything wrong it's most welcome for any correction

 

[hmlahori]

as we kno tht lamp A res=15,
and all the lamps are similr, so the resistnce shud be equal in all of thm.
so when we are closing S2, S3 the resistnce of thes paralle lamps togthr must be 15, and then adding A, it wll b 45.

but here the resistnce is dec.
so we cn cum to a conclusion tht the res. acroos lamp C is less thn 15.

decreasing of resistnce = short circuit of lamp C! :/

i hope i hv solved ur prob:/

does decreasing of a resistance always result in a short circuit and why?

 

[hmlahori]

hmm oky gud luck .my practical tomorow

well gud luck then!

 

[Oliveme]

Please help me with this question In physics paper 23, question 2 part (c). I have no idea about vector triangles. This is the second time I'm posting my question.
http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_s10_qp_23.pdf

Thank you very much.